They’re buildings so energy efficient they don’t need a furnace, an air conditioner or any other kind of active climate control to keep their residents comfortable through the sticky summers and icy winters in many parts of Canada.

“Passive houses” are buildings that rely on insulation, ventilation and heat from their occupants or sun falling on them to maintain the perfect temperature.

In Canada, up until now, they’ve mostly been single-family dwellings — green dream homes for those who can afford them. But now, builders using international passive-house design principles and standards are scaling up to big apartment buildings.

The pioneers on this new frontier aren’t custom home builders for the rich and eco-conscious — they’re non-profit organizations that build affordable housing. And they’re promising more comfortable apartments with extremely low utility bills for some of Canada’s most vulnerable residents.

Graham Cubitt of Hamilton-based social housing provider Indwell spoke about his organization’s passive-house projects at the Buildings Show in Toronto last week. He said most current multi-residential projects trying to incorporate passive-house design are tied to ‘some sort of affordable housing target.’ (Evan Mitsui/CBC)

The first multi-residential passive-house apartment building in Canada was completed just last year. Karen’s Place in Ottawa is a four-storey building with 42 bachelor apartments. Also known as Salus Clementine, the modern-looking building has been fully occupied since February by people with severe mental illness, half of whom were previously homeless.

They pay $489 a month, including utilities, for apartments that are designed to use 66 per cent less energy than if the building were built to the standards of the 2012 Ontario Building Code. Each unit costs about $30 a year to heat.

‘Natural fit’

Lisa Ker, executive director of Ottawa Salus Corp., the non-profit organization that runs Karen’s Place, said the rental rate for people on a disability pension is set by the province, and it hasn’t changed in years despite rising costs. That’s forcing social housing providers to look for ways to save on operating costs like utilities.

‘Building green is a natural fit for the affordable housing sector just out of sheer necessity.’– Lisa Ker, Ottawa Salus Corp.

“Building green is a natural fit for the affordable housing sector, just out of sheer necessity,” Ker told CBC News.